Editing Quantum Conference Key Agreement (section)

==Generic Protocol Structure==
* '''Preparation and distribution:''' A source distributes a multipartite entangled state to the <math>N</math> parties. This step is repeated <math>n</math>
* '''Measurements:''' Upon receiving the systems, the parties perform local measurements and record the classical outcome. The measurements are randomly chosen according to the specifications of the protocol. One of the possible measurement settings is used with higher probability and is called the <u>key generation</u> measurements. The other measurements are used for <u>test rounds</u>, which only occasionally occur. 
* '''Parameter estimation:''' The parties announce the inputs and outputs of their test rounds and of some randomly chosen key generation rounds which are used to estimate their correlation and the potential influence of an eavesdropper. At the end of this step, each party is left with a string of <math>n_{raw} < n</math> bits, which constitute their <u>raw key</u>.
* '''Information reconciliation (error correction):''' The parties publicly exchange classical information in order for the Bobs to correct their raw keys to match Alice's string. In the multipartite case, the information reconciliation protocol needs to account for the correction of the strings of all the Bobs.
* '''Privacy amplification:''' Alice randomly picks a hash function, chosen among a two-universal family of hash functions, and communicates it to the Bobs. Every party applies the hash function to turn her/his partially secure string of <math>n_{raw}</math> bits into a secure key of <math> l < n_{raw}</math> bits.